Bump actions/github-script from 3 to 6 (PowerShell#17842)

Bumps [actions/github-script](https://github.com/actions/github-script) from 3 to 6.
- [Release notes](https://github.com/actions/github-script/releases)
- [Commits](actions/github-script@v3...v6)

---
updated-dependencies:
- dependency-name: actions/github-script
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/backport.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-20.04
     steps:
     - name: Extract backport target branch
-      uses: actions/github-script@v3
+      uses: actions/github-script@v6
       id: target-branch-extractor
       with:
         result-encoding: string
@@ -28,7 +28,7 @@ jobs:
 
           return target_branch[1];
     - name: Post backport started comment to pull request
-      uses: actions/github-script@v3
+      uses: actions/github-script@v6
       with:
         script: |
           const backport_start_body = `Started backporting to ${{ steps.target-branch-extractor.outputs.result }}: https://github.com/${context.repo.owner}/${context.repo.repo}/actions/runs/${process.env.GITHUB_RUN_ID}`;

.github/workflows/rebase.yml

@@ -16,7 +16,7 @@ jobs:
       with:
         fetch-depth: 0
     - name: Post rebase started comment to pull request
-      uses: actions/github-script@v3
+      uses: actions/github-script@v6
       with:
         script: |
           const backport_start_body = `Started rebase: https://github.com/${context.repo.owner}/${context.repo.repo}/actions/runs/${process.env.GITHUB_RUN_ID}`;